package com.xbenben.project.common.utils;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.stereotype.Component;

/**
 * 以静态变量保存Spring ApplicationContext, 可在任何代码任何地方任何时候取出 ApplicaitonContext.
 *
 * @author tcc
 */
@Component
public class SpringContextUtils implements ApplicationContextAware, DisposableBean {

    private static final String ACTIVE_PROFILE_LOCAL = "local";
    private static final Logger logger = LoggerFactory.getLogger(SpringContextUtils.class);
    private static ApplicationContext applicationContext = null;

    /**
     * 取得存储在静态变量中的ApplicationContext.
     */
    public static ApplicationContext getApplicationContext() {
        assertContextInjected();
        return applicationContext;
    }

    /**
     * 实现ApplicationContextAware接口, 注入Context到静态变量中.
     */
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) {
        logger.debug("注入ApplicationContext到SpringContextUtils:{}", applicationContext);
        if (SpringContextUtils.applicationContext != null) {
            logger.warn("SpringContextUtils中的ApplicationContext被覆盖, 原有ApplicationContext为: {}", SpringContextUtils.applicationContext);
        }
        // NOSONAR
        SpringContextUtils.applicationContext = applicationContext;
    }

    /**
     * 从静态变量applicationContext中取得Bean, 自动转型为所赋值对象的类型. 例如：
     * getBean（“custService”），前提是对bean定义别名。
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(String name) {
        assertContextInjected();
        return (T) applicationContext.getBean(name);
    }

    /**
     * 从静态变量applicationContext中取得Bean, 自动转型为所赋值对象的类型. *
     * 例如：getBean(ICustService.class),这种方式，不需要考虑ICustService的别名
     */
    public static <T> T getBean(Class<T> requiredType) {
        assertContextInjected();
        return applicationContext.getBean(requiredType);
    }

    /**
     * Author: xbzhu
     * Mail: toby.zhu@trustlife.com
     * Date: 2017/3/10 10:47
     * Desc: 获取当前环境的激活profile，用于不同环境间区分
     */
    public static String getEnvActiveProfile() {
        if (applicationContext == null) {
            return ACTIVE_PROFILE_LOCAL;
        }
        ConfigurableApplicationContext configurableApplicationContext = (ConfigurableApplicationContext) applicationContext;
        String[] activeProfiles = configurableApplicationContext.getEnvironment().getActiveProfiles();
        if (activeProfiles.length == 0) {
            return ACTIVE_PROFILE_LOCAL;
        }
        return activeProfiles[0];
    }

    /**
     * 清除SpringContextUtils中的ApplicationContext为Null.
     */
    public static void clearHolder() {
        logger.debug("清除SpringContextUtils中的ApplicationContext:{}", applicationContext);
        applicationContext = null;
    }

    /**
     * 检查ApplicationContext不为空.
     */
    private static void assertContextInjected() {
        if (applicationContext == null) {
            throw new RuntimeException("applicaitonContext属性未注入, 请在applicationContext.xml中定义SpringContextUtils,同时set lazy-init is false.");
        }
    }

    /**
     * 实现DisposableBean接口, 在Context关闭时清理静态变量.
     */
    @Override
    public void destroy() throws Exception {
        SpringContextUtils.clearHolder();
    }
}
